2000 Lincoln LS shutters while braking!

2000 Lincoln LS, 126,000 miles, V-8 engine. I recently took a 300 mile roadtrip and on the way back I noticed every time I braked the car would make a loud repettive shutter that was coming from the front of the car, I inspected all the lugs and found them to be tight and the sound persisted. When I knelt next to the car and began to jerk on the tire with both hands, it felt the same on both sides, each tire loose and had about a quarter inch of play side to side? The brakes and rotors are fairly new. Any ideas? Are the wheel bearings shot?